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      <title>Nginx中Master和Worker进程是干什么? - 交互式测验</title>
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    </head>
    <body>
      <div class="main-wrapper">
          <div class="quiz-container">
            <div class="quiz-header">
              <h1>Nginx中Master和Worker进程是干什么? - 交互式测验</h1>
              <p>检验你对文档内容的理解程度</p>
            </div>
            <div id="quiz-content">
                <div class="quiz-body">
                    <div class="progress-bar">
                        <div id="progress-indicator"></div>
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                    <div id="question-container">
                      <p id="question-text"></p>
                      <ul class="options-list" id="options-list"></ul>
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                    <div id="result-container"></div>
                    <div id="hint-container" class="hint-container"></div>
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                <div class="quiz-footer" id="quiz-footer">
                  <button id="prev-btn" class="nav-btn">上一题</button>
                  <button id="hint-btn" class="nav-btn" style="background-color: #ffc107; color: #333; box-shadow: 0 4px 12px rgba(255,193,7,0.3);">提示</button>
                  <button id="next-btn" class="nav-btn">下一题</button>
                </div>
            </div>
          </div>
      </div>

      <script>
        const quizData = [
  {
    "question": "在Nginx的Master-Worker架构中，Master进程的核心职责是什么？",
    "options": [
      "直接处理来自客户端的所有HTTP请求和响应。",
      "负责加载和解析配置文件，并管理Worker进程的生命周期。",
      "记录所有请求的访问日志和错误日志。",
      "执行SSL/TLS加密和解密操作。"
    ],
    "correctAnswerIndex": 1,
    "explanation": "根据文档，Master进程是Nginx的“大脑”和核心管理者，其主要职责包括配置管理（加载、解析配置文件）、进程管理（启动、停止、监控Worker进程）、信号处理和实现无缝升级。它不直接处理客户端请求，这是Worker进程的工作。",
    "source": "文档中「Nginx的进程模型简介」->「2. Master进程的职责」部分",
    "hint": "文档将Master进程比作整个服务器的什么角色？它负责管理和控制，而非执行具体劳动。"
  },
  {
    "question": "管理员希望在不中断服务的情况下更新Nginx的配置，应该执行什么操作？",
    "options": [
      "向Master进程发送SIGHUP信号。",
      "修改配置文件后，等待系统自动检测变更。",
      "向所有Worker进程发送SIGHUP信号。",
      "直接重启Nginx服务（例如使用 systemctl restart nginx）。"
    ],
    "correctAnswerIndex": 0,
    "explanation": "文档中明确指出，当需要更新配置时，可以向Master进程发送SIGHUP信号。Master进程接收到信号后会重新加载配置文件，并平滑地启动新的Worker进程来接管服务，从而实现配置的热加载，避免服务中断。",
    "source": "文档中「Master和Worker进程的交互」->「2. 配置变更和重载」部分",
    "hint": "思考一下，哪个进程负责管理配置，而哪个信号通常用于“重新加载”配置？"
  },
  {
    "question": "如果一个Nginx Worker进程因为异常而崩溃，系统会如何响应以保证服务的稳定性？",
    "options": [
      "Master进程也会随之崩溃，导致服务完全中断。",
      "整个Nginx服务将停止运行，需要手动重启。",
      "剩余的Worker进程会尝试接管崩溃进程的所有连接。",
      "Master进程会监控到该异常退出，并立即启动一个新的Worker进程来替代它。"
    ],
    "correctAnswerIndex": 3,
    "explanation": "这是Nginx高可靠性的关键体现。Master进程的一个重要职责就是监控Worker进程的运行状态。一旦有Worker进程异常退出，Master进程会自动启动新的Worker进程来补充，从而实现故障的自动恢复，确保服务的连续性。",
    "source": "文档中「Master进程职责」->「5. 故障恢复」部分",
    "hint": "Master进程对Worker进程扮演着“管理者”和“监控者”的角色，它是否会放任Worker进程崩溃不管？"
  },
  {
    "question": "Nginx的Worker进程能够高效处理成千上万个并发连接的核心技术是什么？",
    "options": [
      "采用异步非阻塞的事件驱动模型（如epoll、kqueue）。",
      "为每一个新的连接创建一个独立的线程。",
      "通过Master进程进行请求的预处理和分发。",
      "依赖操作系统的多线程调度能力。"
    ],
    "correctAnswerIndex": 0,
    "explanation": "文档中多次强调，Worker进程使用异步的事件驱动模型（基于epoll、kqueue等）。这种模型允许单个进程监听多个I/O事件，当事件就绪时才进行处理，避免了因等待I/O而产生的阻塞，从而极大地提高了并发处理能力。",
    "source": "文档中「Worker进程职责」->「1. 请求处理」部分",
    "hint": "文档中提到了一种与传统阻塞I/O模型相对的高效模型，它是什么？"
  },
  {
    "question": "从安全角度来看，Nginx让Master进程以高权限运行，而Worker进程以降权的低权限用户运行，这种设计主要带来了什么好处？",
    "options": [
      "这种设计简化了配置文件的权限管理。",
      "可以使Worker进程直接访问系统核心资源，提升处理速度。",
      "即使Worker进程被攻击者攻破，攻击者也只能获得低权限，从而限制了对整个系统的潜在破坏。",
      "让Master进程能够更有效地分配内存给Worker进程。"
    ],
    "correctAnswerIndex": 2,
    "explanation": "这是一种权限分离的安全机制。Master进程需要高权限来绑定端口、管理进程等，但实际处理外部请求的Worker进程则以降权用户运行。这样，万一Worker进程存在漏洞被利用，攻击者获得的也只是一个受限的权限，无法对系统造成更严重的损害，有效降低了安全风险。",
    "source": "文档中「Master进程职责」->「6. 安全管理」部分",
    "hint": "思考一下，如果处理外部不可信请求的进程拥有root权限，会带来什么风险？"
  },
  {
    "question": "在Nginx的配置文件中，`worker_processes`指令通常建议设置为什么值以充分利用服务器硬件资源？",
    "options": [
      "等于服务器的CPU核心数。",
      "固定设置为1以获得最佳稳定性。",
      "越大越好，例如设置为128或更高。",
      "设置为服务器可用内存的GB数。"
    ],
    "correctAnswerIndex": 0,
    "explanation": "为了充分利用多核CPU的并行处理能力，通常建议将`worker_processes`的数量设置为等于服务器的CPU核心数。这样每个Worker进程可以被调度到不同的CPU核心上运行，避免了CPU资源的争抢和上下文切换开销，最大化了处理能力。",
    "source": "文档中「配置与优化」->「1. 基础配置」部分",
    "hint": "Worker进程的设计初衷之一就是利用多核CPU，那么它的数量应该和哪项关键硬件指标相关？"
  },
  {
    "question": "Nginx的多进程模型相比多线程模型的一个显著优势是进程隔离。这种隔离特性直接带来了什么好处？",
    "options": [
      "所有进程可以共享一个大型的内存缓存区，提升数据读取速度。",
      "一个Worker进程的崩溃不会影响其他Worker进程，提高了整体服务的可靠性。",
      "进程间的通信（IPC）比线程间通信更快。",
      "可以减少Nginx启动时占用的总内存。"
    ],
    "correctAnswerIndex": 1,
    "explanation": "文档中提到，由于每个Worker进程是独立的，一个Worker进程的崩溃不会影响其他Worker进程的运行。这种进程隔离机制是Nginx高可靠性和稳定性的基石。同时，它也避免了多线程模型中因共享内存而可能出现的复杂的锁竞争问题。",
    "source": "文档中「Nginx的多进程模型优势」->「2. 高可靠性和稳定性」部分",
    "hint": "当一个“工人”出现问题时，其他并行的“工人”是否会受到影响？"
  }
];
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        let score = 0;
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            const totalQuestions = quizData.length;
            const answeredCount = userAnswers.filter(a => a !== null).length;
            const wrongCount = answeredCount - correctCount;
            const skippedCount = totalQuestions - answeredCount;
            const accuracy = totalQuestions > 0 ? Math.round((correctCount / totalQuestions) * 100) : 0;
            const errorRate = totalQuestions > 0 ? Math.round((wrongCount / totalQuestions) * 100) : 0;

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                '<h2>答题报告</h2>' +
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                '<div class="score-card">' +
                '<h3>得分</h3>' +
                '<p>' + correctCount + ' / ' + totalQuestions + '</p>' +
                '</div>' +
                '<div class="score-card">' +
                '<h3>正确率</h3>' +
                '<p>' + accuracy + '%</p>' +
                '</div>' +
                '<div class="score-card">' +
                '<h3>错误率</h3>' +
                '<p>' + errorRate + '%</p>' +
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                '<div class="score-card score-details">' +
                '<table>' +
                '<tr><td>正确</td><td>' + correctCount + '</td></tr>' +
                '<tr><td>错误</td><td>' + wrongCount + '</td></tr>' +
                '<tr><td>未答</td><td>' + skippedCount + '</td></tr>' +
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                '</div>' +
                '</div>' +
                '<div class="report-actions">' +
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                reportEl.remove();
            }
            quizContentEl.insertAdjacentHTML('beforeend', finalScoreHtml);
            document.getElementById('review-btn').addEventListener('click', reviewQuiz);
        }

        function reviewQuiz() {
            const reportEl = document.querySelector('.final-score-container');
            if (reportEl) {
                reportEl.remove();
            }

            document.querySelector('.quiz-body').style.display = 'block';
            document.getElementById('quiz-footer').style.display = 'flex';
            
            currentQuestionIndex = 0;
            loadQuestion();
            updateNavigationButtons(); // Ensure nav buttons are correctly displayed
        }

        // Event Delegation for options
        optionsListEl.addEventListener('click', (event) => {
            if (event.target && event.target.matches('li.option-item')) {
                // Check if the question has already been answered
                if (userAnswers[currentQuestionIndex] === null) {
                    const selectedIndex = parseInt(event.target.dataset.index, 10);
                    selectOption(selectedIndex);
                }
            }
        });

        prevBtn.addEventListener('click', goToPreviousQuestion);
        nextBtn.addEventListener('click', goToNextQuestion);
        hintBtn.addEventListener('click', showHint);
        
        // 初始加载
        loadQuestion();
      </script>
    </body>
    </html>
  